[email protected] wrote:
Hi Richard.
I've used a system similar to yours with some success. Mine, now
dismantled, is detailed at
http://www.g0mrf.com/500kAntenna.htm
It was a 10m mast with a very small 3m top section. Power in 7.5W PEP.
100km was no problem 24/7 with good conditions it made it to ON and
PA. With very good conditions it made it to the Scotish Islands at
apx 800km but that was rare.
The photo shows a variometer in series with a fixed coil in series
with another fixed coil which was connected to ground at the bottom
end. Despite all these turns of wire, the 50 ohm match was only a few
turns up from the ground end.
Hi David
My problem is that I have to carry everything up the hill (or mountain)
myself along with all the other things needed for
hillwalking/mountaineering. So far I have realised that a 200ft L is not
a suitable configuration. Alan G3NYK has suggested a T with 200ft top
instead - that will keep everything a bit further from the ground. Kites
are fun and obviously effective but the right conditions rarely occur
for kitebourne operations - I will be trying them but I need something
that can be used in a wide variety of weather and local conditions.
Incidentally, my experience is that hilltops often suffer from very
turbulent airflows which makes kite flying very tricky. Gun (the hill
that I was on yesterday) is especially bad in that respect as it often
seems to have some sort of windshear over it making launching a kite a
real problem - been there, got the T shirt! My children - who are
usually tasked with flying the kite - refuse to attempt it on Gun any
more due to my rather poor response when the kite crashes mid-QSO...
The microwavers here will be smiling as it took them a while to realise
that my sort of portable is very different from car-supported operations
in a field. That being said I eventually developed a fully portable and
very effective 10G system that can be backpacked anywhere. I will manage
the same on 500kHz given time I expect.
73
Richard
G3CWI
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